ATF fluid flush - tiptronic B5 VW Passat and Audi
Automatic transmission fluid flush on VW Passat with tiptronic automatic transmission
This article shows how to drain and refill the ATF on a VW Passat. This basic procedure also works on Audi A4, A6 and many other ZF transmissions.
The automatic transmission on your VW Passat TDI is ZF brand, the 5 speed automatic transmission is 01v. The TDI transmission's code is GMR (gearing is different to account for low engine rpm). The suggested fluid change interval is between 50-80,000 miles or 8 years, depending on use. 65,000 miles (100,000 km) should be OK for the average car. The basic procedure can also be used on Audi A4, A6, A8, BMW, Porsche, or any other similar ZF transmission. Just adjust the fluid level for your transmission's requirements. Parts like filters are very easy to find because they were shared across many vehicles and the transmission is considered reliable. There have been a few torque converter problems on this application.
The official maintenance schedule does not give any suggestion on when to change the fluid because it (and the dealer) will say it has lifetime fluid and is not serviceable. What they mean is that when old fluid causes excess wear or leaks out, it ends the economically useful lifetime of your car, so come back and buy a new car. Lifetime can often mean it lasts for the lifetime of your car's warranty. In theory, the fluid can lubricate well for a very long time without issue. The problem is that it gets contaminated with water or fine particles or leaks/seeps out. Below is a picture from an Audi transmission pan with lifetime fill showing metal shavings stuck to a magnet. Something was wrong with the transmission and changing the fluid may have prevented further damage.
Below is a pan with normal wear and tear - there's a grey metal slurry on the bottom and metal chia-pets stuck to the magnets.
You may hear that if a high mileage car (well over 100,000 miles) has never had the ATF changed then you shouldn't change it because the new fluid will cause leaks or slipping. The reason why this sometimes happens (usually doesn't) is because residue built up on the gaskets and seals is preventing external and internal seepage and leaks. The dirty fluid also provides some internal friction which prevents slipping. The fresh detergents in the new fluid cleans the residue out. On the other hand, not changing the fluid could also cause future problems. While the best thing is to regularly change the fluid, I suggest changing it even on high mileage cars because not changing it will result in more problems. Draining/refilling the old fluid also doesn't change all of the fluid because some will be left in the torque converter and sitting in the corners. Using an ATF flushing machine will change all the fluid and may increase the chance of having problems.
If you are wary of a slipping transmission, drain/refill the fluid using the procedure below and just leave it alone until the next service. If you insist on getting as much fresh fluid in there as possible, wait until the next oil change time and drain/refill it again. The old fluid will be diluted enough. If you want to immediately flush all the fluid due to contamination or other reasons, you'll have to change the fluid twice to get a decent flush. There's old fluid in the torque converter, pumps, lines to the radiator, and the radiator. A professional with a flush machine with the correct VW/Audi fluid can quickly do a full flush. They work by connecting inline with the transmission lines and running the transmission to circulate the fluid. Since the fluid doesn't follow a strict circuit in the transmission, this will require about 10 liters to get a full flush. New fill capacity is 9 liters. The radiator has ATF lines on it because it cools both the transmission fluid and engine coolant.
The service manual says that the drain and fill plug seals must be replaced each time. The drain plug seal is only sold with a new plug so I just reused mine on a few different cars with this tranmsmission and they've never leaked. If you're afraid it will leak, just apply a light smear of gasket maker low on the threads. You don't want excess gasket maker getting into the ATF and there's a filter on the fluid intake just in case.
Caution: In a manual transmission, the differential and transmission share gear oil. In your automatic transmission, the differential and transmission are sealed off from each other and use different fluids!
ATF fluid flush parts and tools
(click on links to compare current pricing)
new capacity: 9.0 liters of fluid, VW# g 052 162 a2 (for 5 speed "01v" tiptronic transmission, your Passat TDI uses the "01v gmr")
I prefer OEM or Pentosin ATF. ZF (they make the transmission, not VW) recommends any LT71141 spec fluid like Valvoline Dex/Merc, Valvoline MaxLife Dex/Merc, or Valvoline Mercon V. These are also reported to work fine.
transmission filter, VW# 01v 325 429
filter gasket, VW# 01v 325 443
transmission pan gasket, VW# 01v 321 371
fill plug seal VW# 01v 321 379
drain plug seal (only comes with new plug) VW# 02v 321 377
VW tool 1924 or equivalent (see bottom for my method)
8, 17mm allen / hex bit
vinyl/nitrile/rubber gloves to protect your hands against ATF
jack stands, hydraulic jack, wheel chocks, safety glasses
kitty litter or driveway absorber gravel (to soak up stains)
VCDS cable from Ross tech
First start the engine and warm it up until the transmission pan is luke warm. The procedure in the factory service manual specifies a test temperature of 95oF-113oF. Use a Ross tech VCDS cable to measure this. Shut the engine off before that temperature is reached so that it's at the test temperature later during refill.
Engage the parking brake, jack up the car, rest car securely on jack stands at the factory jack points, and make sure the car is safe and secure before doing anything else. The car must be level, otherwise the fluid level will not be accurate. I use wheel blocks in addition to jack stands to support the car as shown in 1000q: wood blocks. Disclaimer - these are not a substitute for jack stands on the factory jack points.
Draining the fluid
Clean the area around the drain (8mm allen bit) and fill plug (17mm allen bit).
Before you remove the drain plug, always loosen the 17mm fill plug to make sure you can refill the transmission after draining it! Then remove the 8mm transmission drain plug. Make sure you are not removing the engine oil drain plug! The engine oil pan is silvery aluminum, under the engine, should be covered by the splash shield, and uses a regular bolt, not an allen head bolt. The transmission pan is painted black and is under the transmission.
Let the fluid drain out and replace the plug. This will remove most of the fluid in the transmission - some will still be in the torque converter, pumps, radiator, etc. If you're worried about driveway stains, a sheet of cardboard can act like a placemat under the catch pan.
Optional: open the transmission coolant lines to drain the radiator and lines. The union is in front of the driver's side oil pan. Open the lines and drain them.
The fluid will stain your driveway and melt asphalt so after using paper towels to dab off the standing fluid, put some kitty litter or driveway absorber onto the stain. Step on the gravel and crush it into the stain - this will absorb most of the stain. Do not dump old ATF onto the ground! If you can't find a disposal for the used ATF, earth911.com has a search function for your local car fluids disposal.
Replacing the filter
Unless there is a problem with the transmission, the filter is normally a 100,000-150,000+ mile filter. The filters don't get very clogged. However, removing the filter lets you change more fluid and clean off the sludge and magnets on the bottom of the pan. If you are going to change the filter or remove the transmission pan, stick some strong magnets on the bottom of the steel pan a few days before to catch more metal sludge.
After draining the fluid, remove the T27 torx bolts around the edge of the steel pan and remove the pan. Clean off the magnets and wipe the bottom of the pan clean. It's normal to find a grey slurry on the bottom and some fuzzies on the magnets. Solid chunks of metal would be abnormal.
To remove the filter, remove the T40 x2 torx bolts holding it, blue arrows below. (pictured below is a transmission out of the car)
Make sure the old filter seal is removed. Wet the new oil seal with ATF before installation.
Clean any old paper gasket off the sealing surfaces and replace the pan. Torque the transmission pan bolts to about 7 ft-lbs in a diagonal pattern to keep the pan flat. Then move around and retighten all the bolts to "snug but not overtight". 11 ft-lbs is my guess on the final torque.
Refilling the automatic transmission fluid
WARNING: the engine must be running to top off the fluid. Make sure the front splash shield is in place and secure to cover the belts at the front of the engine before starting the engine. While the engine is running, take care to keep all hands/tools/persons away from the moving belts or fans at the front of the engine (AC belt, serpentine belt, coolant fan) and away from the hot exhaust pipes while under the car! Moving belts could easily rip off your hand, loose hair/clothing, or fingers if they get caught in the belts or fan! If you do not have adequate clearance under the car to comfortably stay away from the belts at the front of the engine, do not attempt this job! See the TOS Agreement for the full legal disclaimer.
With the engine off, make sure the front splash shield is securely in place. Then put a drip pan or piece of cardboard underneath the fill hole to catch the dribbles.
There are a few ways to get the fluid back in. You could use a gravity pump (siphon) or funnel, where the bottle is higher than the fill hole and connected with a hose, but because you're underneath the car you would need a very long hose which wastes fluid. You can use a hand pump designed to force fluid out of a container. This keeps the hose short but you're going to move a lot of fluid and it's awkward pumping under the car. I use compressed air to force the fluid into the fill hole because it's easier and faster than a hand pump.
The reason why you can't use a short funnel is because the fill hole is on the bottom and you need fluid to go up through the fill hole. See how the tip needs to be bent at least 90o through the hole in the fill hole cap? (The drain plug is in place). The method below uses a coat hanger through the hose to bend the tip as needed. It also helps avoid fluid drips down the outside of the hose.
To use the compressed air method of adding fluid, poke a smooth round hole through the bottle cap and at the top of the bottle (smaller is better for a tight air seal), and a small hole (again, smaller is better) in the top of the bottle, marked by the green arrow in the below picture. I use a thin pointed pair of pliers and rotate it to poke a small, tight hole without sending shavings into the bottle. You could also use a small screwdriver.
Stick the hose into the bottom corner of the bottle. Make sure the hose has at least 1/4 diameter, otherwise the fluid will have a hard time moving through it. The dashed line shows the hose inside the bottle. If the hose end is above the fluid level you'll get foam. Too much foam will cause underfilling due to air bubbles. If this happens, let it settle down and overfill it slightly.
The hose has a coat hanger in it bent into an s-shape (so it stays in place) with a 90o hook at the end so I could use it for various manual and automatic transmissions and to minimize dripping. If the compressed air input hole is below the fluid level obviously the fluid will leak out. Below is another style of fill tip by user wizard - a piece of metal hose was split to let it hang in place and inserted into a hose. A sharper angle could help with dripping but as long as the hose tip is angled down it should be OK.
Regulate the compressed air pressure down to a reasonable amount, just enough to get the fluid flowing at a reasonable rate. Excess pressure could cause the bottle to pop so start low and then increase the pressure as needed.
Now press the compressed air nozzle into the hole. Warning! Do this step last because if you accidentally press the trigger on the compressed air nozzle before the hose is in the fill hole or before you transfer the cap/hose to the next bottle, your expensive fluid is now all over the ground. Apply gradually increasing amounts of pressure until the fluid is gone. If the bottle stretches a little it's okay. If you think it's going to pop, stop applying pressure. I put my gloved hands around the bottle cap and nozzle just in case the bottle cap pops off - it's never happened to me yet but be careful. As always, wear protective safety goggles.
When you go to the next bottle, move the cap w/hose to the next bottle and poke another air intake hole in the next bottle. Don't let the hose touch the ground because it will get dirty. If it gets dirty just thoroughly wipe it off. Like this tip? There are many more tips for the mechanic at 1000q: basic mechanic's tips.
Once fluid begins to drip out of the fill hose, stop and proceed to the next step.
WARNING: the engine must be running to top off the fluid. Make sure the front splash shield is in place (picture above was for illustration) and secure to cover the belts at the front of the engine before starting the engine. While the engine is running, take care to keep all hands/tools/persons away from the moving belts or fans at the front of the engine (AC belt, serpentine belt, coolant fan) and away from the hot exhaust pipes while under the car! Moving belts could easily rip off your hand, loose hair/clothing, or fingers if they get caught in the belts or fan! If you do not have adequate clearance under the car to comfortably stay away from the belts at the front of the engine, do not attempt this job! See the TOS Agreement for the full legal disclaimer.
Have a helper start the engine with the brakes firmly applied and the wheels chocked as necessary. Have them slowly move the shifter through the gears while you add fluid. When VCDS shows a transmission fluid temperature of 95oF-113oF (lukewarm oil pan) and fluid runs out of the fill hose with the engine at idle and transmission in park put the fill plug back (engine is still running). A lower temperature is better since the fluid will heat up fast and slight overfilling (won't happen if you're anywhere near 85oF) is much better than under-filling. There can be as much as 1.0L capacity difference between a warm and cold transmission. The car will still run fine if it's a tiny bit overfilled so if the car isn't perfectly level on jack stands, make sure it's tilted to overfill the transmission, not underfill it. In the above picture the rear wheels were also on wood blocks so the car was level. Remember, the ATF is also being warmed by the engine in the radiator.
Once the fill plug is back you can shut off the engine. After you're done, hang the hose with paper towels on the end and let it drip dry. If you need any more clarification on these tips on how to replace your VW Passat TDI ATF, free to sign up comment at the VW TDI myturbodiesel.com forums.
The service manual says that the drain and fill plug seals must be replaced each time. The drain plug seal is only sold with a new plug so I just reused it and I've never had a leak. If you are afraid it will leak you can use a light smear of gasket maker low on the threads. You don't want excess gasket maker getting into the ATF and there's a filter on the fluid intake just in case. Inspect the car a few days later for leaks either way.
DIY full flush
If you DIY full flush, I would also disconnect the ATF lines at the radiator or union on the driver's side. If you do this and change the filter, it will get about 2/3 of the old fluid out. You'll use about 6 liters after accounting for spillage. Drive around for a week/month/next oil change, and drain/refill the fluid one more time (you'll use about 4 liters), and there'll be enough fresh fluid in there to dilute any old fluid. About 10 liters (to account for spillage) is enough. Use a clean container to catch the fluid the second time you drain it so if you're short some fluid you can put it back.
Changing the fluid in the torque converter manually
The only way you can get the fluid out of the torque converter without the fluid pumps running is to remove the transmission. The torque converter will slide straight out. Use a hand vacuum pump like a mity-vac or VW tool 1358 a/1 oil extractor and probe to suck out as much fluid as possible (shown below). Then add some fluid, mix and shake it around, then suck all the fluid out. Repeat until the fluid that comes out is relatively clean. There is no drain valve.
To drain the rest of the fluid in the transmission, tilt it around to let the fluid that's trapped in the corners drip out.
17mm fill plug - 59 ft-lb *NOTE- there's a typo in the Bentley manual, they reversed Nm and ft-lb, 59 ft-lb or 80 Nm is the correct torque
8mm drain plug - 30 ft-lb
ATF filter bolts - 5 ft-lb (official spec is 53 inch lbs)
transmission pan bolts - first tighten them all to 7 ft-lbs in a diagonal pattern, then go around again so that they are snug but not too tight. 11 ft-lbs is my guess on the final torque.
Changing final drive gear oil, the differential
Drain and refill the gear oil separately from the automatic transmission fluid. The differential takes .75 liters (.8 quart) of VW# g 052 145 s2 gear oil (75w90).
With the car level and engine warm, remove the 8mm plug on the side of the differential. Suck out the old fluid and refill. Let the gear oil sit for a few minutes to settle down and fill the holes/cracks. Oil level should be at the bottom of the fill hole. Torque spec is 22 ft-lb.
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